docs: add sample for getting started with BQML

[DevStephanie]

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Fixes #<issue_number_goes_here> 🦕

[snippet-bot]

Here is the summary of changes.

You are about to add 1 region tag.

• samples/snippets/bqml_getting_started_test.py:19, tag bigquery_dataframes_bqml_getting_started_tutorial

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[tswast]

This comment has nothing to do with BigQuery ML models. Please fix.

Note: The important thing here is that we're taking our trained model and writing it to a permanent location.

[DevStephanie]

Agreed, corrected.

[tswast]

FYI: The comment is still talking about tables not models. I'll make a comment with a suggested edit.

[tswast]

We can remove this file for now. Let's do a separate PR for the K-Means tutorials.

[DevStephanie]

Corrected.

[tswast]

This file still needs to be deleted.

[tswast]

FYI: We're getting

E           google.api_core.exceptions.BadRequest: 400 Concurrent update on same model: bigframes-dev:bqml_tutorial.sample_model is not supported. Share your usecase with the BigQuery DataFrames team at the [https://bit.ly/bigframes-feedback](https://www.google.com/url?q=https://bit.ly/bigframes-feedback&sa=D) survey.

failure in our test suite: https://fusion2.corp.google.com/invocations/8a7513c8-e7c9-4b5b-82fe-9a83c176fbc1/targets/bigframes%2Fpresubmit%2Fe2e/log

I think we'll need a test fixture for this to create a temporary place for the model and clean it up when the test finishes.

1. Create a file called samples/snippets/conftest.py.

2. In the conftest.py file you create, add a fixture called random_model_id, similar to this one: https://github.com/googleapis/python-bigquery/blob/f804d639fe95bef5d083afe1246d756321128b05/samples/snippets/conftest.py#L101-L111 except it'll call delete_model(...) instead of delete_table(...).

   You'll also need to add "prefixer" https://github.com/googleapis/python-bigquery/blob/f804d639fe95bef5d083afe1246d756321128b05/samples/snippets/conftest.py#L21 and bigquery_client fixture https://github.com/googleapis/python-bigquery/blob/f804d639fe95bef5d083afe1246d756321128b05/samples/snippets/conftest.py#L33-L36

3. Update your code sample to use the new random_model_id fixture.

   Look how we do it in the remote functions test:

   python-bigquery-dataframes/samples/snippets/remote_function.py

   Lines 17 to 23 in 81125f9

   	your_gcp_project_id = project_id
   	# [START bigquery_dataframes_remote_function]
   	import bigframes.pandas as bpd
   	# Set BigQuery DataFrames options
   	bpd.options.bigquery.project = your_gcp_project_id

   but instead you'll be setting your_model_id = random_model_id and calling

   model.to_gbq(
       your_model_id,  # "project.dataset.model_id" or "dataset.model_id"
       replace=True,
   )
   

[tswast]

Let's use bigquery_dataframes_bqml_getting_started for our region tags.

[ghost]

Sounds great, will make edits now.

[tswast]

Revert this